Prevention and treatment of bone and cartilage damage or disease

ABSTRACT

Compositions and methods for the prevention and/or treatment of conditions involving disease or damage in mammalian cartilage and bone, using mesenchymal stem cells isolated with anti-integrin α10 antibodies are disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. Patent ApplicationNo. 16/519,179, filed Jul. 23, 2019, which is a United Statesnon-provisional continuation application filed under 35 U.S.C. § 111(a)of PCT Application No. PCT/EP2018/052104, filed on Jan. 29, 2018, whichclaims priority to United States Application No. 62/451,372, filed onJan. 27, 2017, all of which are incorporated by reference in theirentirety.

The present invention relates to compositions and methods for theprevention and/or treatment of conditions involving disease or damage inmammalian cartilage and bone, using mesenchymal stem cells isolated withanti-integrin α10 antibodies.

BACKGROUND

Articular cartilage is highly prone to injury and pathologicaldegeneration. Once damaged, articular cartilage generally does not heal,or heals only partially under certain biological conditions. Damageleads to further degradation of the cartilage, and cartilage breakdownproducts initiate inflammation, resulting in further degradation ofcartilage that in turn drives the inflammation, thus creating a viciouscycle¹. There is a well-known link between early cartilage traumas, fromsports injuries, for example, and later development of osteoarthritis(OA)².

Cell therapy is a promising method for tissue regeneration. A series ofstudies in animals and humans have shown safety and efficacy for thetreatment of various diseases, including cartilage damage usingmultipotent mesenchymal stromal cells (MSCs)^(6,7). Therapeutic effectsof MSCs are believed to be multifactorial. MSCs can directlydifferentiate into the specific cell type of the tissue to beregenerated, but also modify the microenvironment by producingextracellular matrix, cytokines and growth factors, recruit andstimulate endogenous stem cells, and have immunosuppressive effects⁸.Transplantation of MSCs for cartilage repair and regeneration istherefore a promising strategy given the potential of these cells todifferentiate into chondrocytes⁶. Typically, stem cell preparations arecomplex mixtures of cell types or cells with varying capacities ofdifferentiation. Because of their plasticity and large differentiationpotential it is important that preclinical and clinical studies areconducted with well-defined cells. Characterization of MSCs by qualitycontrolled biomarkers is crucial for good efficacy but also for safe useof the cells as therapeutic agents. The international society forcellular therapy proposed the cell phenotypes plastic adherence,trilineage differentiation potential, as well as expression or absenceof the surface markers CD73, CD90, CD105 respective CD45, CD34, CD14 orCD11b, CD79α or CD19, HLA-DR to be minimal criteria for human cells tobe defined as MSCs⁹.

In veterinary patients, three approaches based on MSCs are currentlyused for the treatment of tendon, ligament, or cartilage/joint injuriesin horses or dogs¹⁰. The three cell types used are: a culture expandedcell population derived from bone marrow (BM) aspirate (most of theclinical studies have used this cell population), a concentrated mixedcell population derived from BM aspirate, and a mixed nucleated cellpopulation derived from adipose tissue (AT). All three types of cellscan be of autologous (own) or allogeneic (donor) origin. None of themhave been very well defined.

To improve cartilage repair with MSCs, two variables are believed to beimportant for satisfactory results; the quality and number of MSCs to beinjected and the administration method. It is now evident that cellsselected by the international society for cellular therapy criteria,still are a heterogeneous population. A solution to the MSC qualityproblem could be to use a defined population of MSCs with expression ofspecific candidate potency markers¹¹.

Integrin alpha10 beta1 (α10β1) was originally identified as a collagentype II binding receptor on chondrocytes and has been shown to have acritical role in skeletal development¹². It is abundantly expressed onchondrocytes and is present in a sub-population of human MSCs.Antibodies targeting integrin α10β1 can be used to identify,differentiate, and isolate MSCs from a mixed cell population (seeWO03/106492). Extended culturing of chondrocytes or transforming growthfactor (TGF) β1 treatment leads to dedifferentiation accompanied by adecrease in the chondrocyte-specific integrin α10 level. In contrast,bone morphogenetic protein (BMP)-2 administration to the culture mediumstabilizes the chondrogenic phenotype and induces high levels ofintegrin α10 expression¹³. In suspension culture, the formation ofchondrocyte aggregates with distinct pericellular matrix requires α10β1integrin-collagen type II interaction¹⁴. Moreover, it has beendemonstrated that integrin α10β1 expression correlates with improvedchondrogenic differentiation potential of human BM derived MSCs¹⁵.

It is known that joint injury substantially increases the risk ofosteoarthritis (OA), a phenomenon called post-traumatic osteoarthritis(PTOA). However, no preventative or disease modifying treatments areavailable for treatment of OA or PTOA, and current treatments alleviatesymptoms without preventing the onset of disease and/or diseaseprogression or worsening. Thus, there is a substantial need for means toprevent development of OA following injury or trauma.

SUMMARY

The present inventors have for the first time demonstrated in vivo thatintegrin α10 enriched populations of MSCs administered to mammalsafflicted with bone or cartilage injuries, can be used to prevent andtreat conditions associated therewith, or resulting therefrom.

Hence, in one aspect, the present disclosure is directed to an enrichedintegrin α10^(high) population of MSCs for use in a method of preventionor treatment of subchondral bone sclerosis traumatic joint injuries,and/or degenerative disc disease, wherein at least 60% of the cells ofthe population of MSCs express integrin α10 subunit, and wherein saidMSC is selected from the group consisting of a mesenchymal stem cell, amesenchymal progenitor cell, and a mesenchymal stromal cell.

A further aspect of the present disclosure is directed to an enrichedintegrin α10^(high) population of MSCs for promoting or inducingfracture healing, wherein at least 60% of the cells of the population ofMSCs express integrin α10 subunit, and wherein said MSC is selected fromthe group consisting of a mesenchymal stem cell, a mesenchymalprogenitor cell, and a mesenchymal stromal cell.

One aspect of the present disclosure is directed to a use of an enrichedintegrin α10^(high) population of MSCs wherein at least 60% of the cellsof the population of MSCs express integrin α10 subunit, and wherein saidMSC is selected from the group consisting of a mesenchymal stem cell, amesenchymal progenitor cell, and a mesenchymal stromal cell, for thepreparation of a medicament for the prevention or treatment ofsubchondral bone sclerosis traumatic joint injuries, and/or degenerativedisc disease.

A further aspect of the present disclosure is directed to a method oftreating and/or preventing subchondral bone sclerosis traumatic jointinjuries, and/or degenerative disc disease in a subject comprisingadministering an enriched integrin α10high population of MSC to asubject at risk for, or having, subchondral bone sclerosis, wherein atleast 60% of the cells of the population of MSCs express integrin α10subunit, and wherein said MSC is selected from the group consisting of amesenchymal stem cell, a mesenchymal progenitor cell, and a mesenchymalstromal cell, thereby treating and/or preventing subchondral bonesclerosis and/or osteochondral damage.

One aspect of the present disclosure is directed to a method ofmanufacturing an enriched integrin α10^(high) population of MSCs asdescribed herein, the method comprising,

-   -   a. isolating a population of stem cells from adipose tissue,        bone marrow, synovial membrane, cord blood, Wharton's jelly, or        amniotic fluid;    -   b. culturing the isolated cells in a plastic culture vessel;    -   c. discarding non-adhered cells;    -   d. inducing integrin α10 expression by adding culture media,        wherein the culture media is a serum-free media or a media        comprising mammalian serum, and wherein the culture media        comprises platelet lysate and/or platelet lysate components,        and/or growth factors;    -   e. selecting the cells that express integrin α10, and    -   f. expanding the selected cells, thereby producing an enriched        integrin α10^(high) population of MSCs.

DESCRIPTION OF DRAWINGS

FIG. 1A, FIG. 1B, FIG. 10 , FIG. 1D, FIG. 1E, FIG. 1F, FIG. 1G, FIG. 1H,FIG. 11 , and FIG. 1J provide typical FACS profiles of bone marrow (BM)and adipose tissue (AT) derived mesenchymal stromal cells (MSCs). Cellswere marked with antibodies recognizing the cell surface markers CD44,CD45, CD90, CD105, and MHC class II. The left panel shows BM derivedMSCs, and the right panel shows AT derived MSCs. Antibody-labeled cellsand negative control cells (not labeled with antibody) are shown.

FIG. 2A and FIG. 2B show typical expression profiles of integrin α10β1on cultured equine MSCs derived from BM (A) and AT (B). Integrin α10labeling intensity was plotted against sidescatter. Both types of MSCsexpressed integrin α10β1, but a larger proportion of BM derived MSCswere positive for integrin α10 expression.

FIG. 3A and FIG. 3B show AT derived MSCs sorted into two distinct cellpopulations by fluorescence activated cell sorting (FACSAria) using aspecific anti-integrin α10 mAb. Integrin α10 labeling intensity wasplotted against sidescatter. MSCs gated as integrin α10^(high) aredenoted by blue color (on the right) and MSCs gated as integrinα10^(low) are denoted by yellow color (on the left) (A). Cells gated asintegrin α10^(high) were subsequently allowed to adhere to plastic andstained with an antibody directed against integrin α10. Cell nuclei werecounterstained with DAPI (B).

FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D show immunohistochemical analysisof pellet mass cultures made on cryosections from unsorted and sorted(integrin α10^(high) or integrin α10^(low)) AT-MSCs. Cryosections fromfive differentiation experiments were labeled with anti-type II collagenantibodies and the immunohistochemical color reaction quantified usingImageJ 1.50i software (A). Typical type II collagen expression patternsand levels are shown for cryosections from central regions of pelletmass cultures using unsorted cells (B), sorted integrin α10^(high) cells(C), or sorted integrin 10^(low) clls (D). Collagen type II labelingshowed intermediate labeling of collagen type II in the unsortedpellets, strong labeling of collagen type II in the sorted integrin10^(high) pellets while collagen type II was lower in the integrinα10^(low) pellets indicating a positive effect of integrin α10 onchondrogenic differentiation.

FIG. 5 shows gene expression analysis of pellet mass cultures made withRNA from unsorted and sorted (integrin α10^(high) or integrin α10^(low))AT-MSCs. GAPDH was used as endogenous control and unsorted cells wereused as reference sample for ΔΔCt calculation. The results show lowerexpression of type I collagen and higher expression of type II collagenand aggrecan in integrin α10^(high) pellets compared to integrinα10^(low) pellets, indicating better chondrogenic differentiation in thepellets from integrin α10^(high) sorted cells. Bars show mean±SD.

FIG. 6A, FIG. 6B, FIG. 6C, and FIG. 6D show the homing capacity ofnon-sorted and integrin α10 sorted cells to intact or damaged cartilage.Cells expressing higher levels of integrin α10 (a10^(high) cells) arebetter at homing to the region of interest for cartilage repair. Barsrepresent mean±S.D.

FIG. 7 shows that the subchondral bone sclerosis component score in6-month control limbs was significantly higher than treated limbs at6-months and significantly higher than treated or control at 6 weeks andstudy entry (0 days). Bars represent mean±S.E. Groups that do not sharea common letter are significantly different from each other at p<0.05.

FIG. 8 shows that prostaglandin E2 (PGE-2) levels were greater intreated limbs compared to control limbs at 9/11 time points andsignificantly greater in treated limbs at 28-days post op compared tocontrol limbs at time 0, 4, 42, 56, 126, and 154 days. Data arepresented as mean±S.E. Groups that do not share a common letter aresignificantly different at p<0.05.

FIG. 9 shows that procollagen II C-propeptide (CPII) levels, indicatingincreased collagen type II synthesis, were higher in treated compared tocontrol limbs at several time points and significantly greater intreated and control limbs at 7 and 14 days compared to time 0 and studyend (day 154). Data are presented as mean±S.E. Groups that do not sharea common letter are significantly different at p<0.05.

FIG. 10 shows results of the C2C ELISA. The C2C ELISA measures theneoepitope at the C-terminus of 3/4 peptide which is generated throughcleavage of typed II collagen by collagenases. In both treated andcontrol groups, C2C significantly increased from the impact surgerythrough day 14, and then decreased throughout the study to values notdifferent from time 0. Data are presented as mean±S.E. Groups that donot share a common letter are significantly different at p<0.05.

FIG. 11A and FIG. 11B show histology of osteochondral sections.Talocrural (hock) joints were prepared for histology and sections werestained with Safranin-O/Fast Green (A). Normal levels of proteoglycanscould be seen in non-impacted areas of the cartilage both in treatmentand control limbs. At impacted areas, differences in proteoglycancontent and chondrocyte organization could be seen in some horses.Adjacent, sections were labeled with antibodies directed against type IIcollagen (B). Normal levels of type II collagen could be seen innon-impacted areas of the cartilage both in treatment and control limbs.At impacted areas differences in type II collagen content and expressionpattern could be seen in some horses.

FIG. 12 shows that cartilage fibrillation was significantly less(better) in treated limbs at study end (6-months) compared to controllimbs. Bars represent mean±S.E., p<0.039, paired-t-test, one-tailed.

FIG. 13 shows India ink staining. Post mortem, India ink was applied tothe articular surface, and digital photographs were obtained. India inkcontains particulate carbon, and adheres to area of the articularsurface where the cartilage integrity is compromised. Arrows point toimpact areas where India ink adhesion can be seen as a black stain ondamaged cartilage. More India ink adhered to control limb cartilagesurfaces than to treatment limb cartilage surfaces indicating abeneficial effect of the treatment.

FIG. 14 : Immunosuppression assay showing equine integrin α10 selectedMSCs isolated from adipose tissue have an immunomodulatory capacity on Tcells, demonstrated as a decrease in lymphocyte proliferation withincreasing ratios of MSCs to PBMCs. The greatest immunosuppressiveeffect was generated at one MSC to one PBMC ratio.

DETAILED DESCRIPTION

Definitions

“Anti-integrin α10 antibody” or “anti-integrin α10 subunit antibody” isused herein interchangeably to refer to an antibody capable ofrecognizing and binding to at least the integrin α10 subunit of theheterodimeric protein integrin α10β1. These antibodies may be antibodiesthat recognize an epitope of the heterodimeric protein integrin α10β1.wherein the epitope comprises amino acid residues of both the integrinα10 and the integrin β1 subunit.

The term “break” as used herein in relation to a bone injury or damagerefers to a bone fracture, which is a medical condition in which thereis a damage in the continuity of the bone. A break may be the result ofhigh force impact or stress, but also of a minimal trauma injury as aresult of certain medical conditions that weaken the bones, such asosteoporosis, bone cancer, or osteogenesis imperfecta, where the breakor fracture can also be called pathologic fracture.

The term “bruise” as used herein in relation to a bone injury or damagerefers to a traumatic injury to a fibrous tissue of a bone that is lesssevere than a bone fracture. A bone bruise may be cause by a traumaticinjury to a bone or joint as well as by arthritis.

The term “identifying” as used herein refers to the action ofrecognizing a cell as being a certain type of cell, e.g. a MSC or achondrocyte. An alternative term to identifying is “detecting”, which isused herein with the same meaning.

“Integrin β10” or “integrin alpha-10” as used herein refers to the α10subunit of the heterodimeric protein integrin α10≢1. This denotationdoes not exclude the presence of the integrin β1 subunit bound to theintegrin α10 subunit thus forming the quaternary structure of integrinα10β1 heterodimer. The human integrin α10 chain sequence is known andpublicly available at GenBank™/EBI Data Bank accession number AF074015and has been described in Camper et al J. Bio. Chem. 273:20383-20389(1998).

The term “malalignment of a bone” as used herein refers to adisplacement of a bone out of line in relation to joints.

The terms “isolating”, “sorting” and “selecting” as used herein refer tothe action of identifying a cell as being a certain type of cell andseparating it from cells that do not belong to the same cell type or toanother differentiation state. Usually, isolation refers to a first stepof separation, whereas “selection” is more specific and for exampleperformed with the help of an antibody.

“Mesenchymal stem cells” or “MSCs” as used herein refers to multipotentstromal cells as defined by The Mesenchymal and Tissue Stem CellCommittee of the International Society for Cellular Therapy (seeDominici M et al., Cytotherapy. 8(4):315-7 (2006)). MSCs must beplastic-adherent when maintained in standard culture conditions, andmust express CD105, CD73 and CD90, and lack expression of CD45, CD34,CD14 or CD11b, CD79alpha or CD19 and HLA-DR surface molecules. MSCs musthave the capacity to differentiate to osteoblasts, adipocytes orchondroblasts in vitro.

“Osteoarthritis” or “OA” as used herein refers to a joint diseasecharacterized by breakdown of joint cartilage. OA may also be referredto as wear-and-tear arthritis, degenerative joint disease anddegenerative arthritis. Symptoms of OA include joint swelling, pain, anddecreased range of motion. Joints commonly affected by OA include thehand, large toe, wrist, neck, back, knee, and hip. In OA, cartilage maybecome stiff and lose its elasticity, or cartilage may wear away in someareas. In advanced cases of OA, the bones of a joint may rub againsteach other as joint surface cartilage is lost.

“Post-injury arthritis,” “post-traumatic arthritis,” or “PTOA” as usedherein refers to OA caused by a previous injury, damage, or trauma. Thiscondition may occur in any joint. Injury may damage the cartilage and/orbone of a joint, and this can cause cartilage to wear out more quickly.Conditions like continued injury or excess body weight may cause oraccelerate the development of PTOA.

The term “sports injury” as defined herein refers to an injury thatoccur while exercising. Sports injuries can be both of traumatic natureand also due to overuse and repetitive stress.

The term “sprain” as used herein in relation to a bone injury or damagerefers to a stretch and/or tear of a ligament. A sprain is usuallycaused by an injury that stresses a joint and overstretches or evenruptures supporting ligaments, for example a twist.

The term “tear” as used herein in relation to a bone injury or damagerefers to rupturing of one or more of the fibrocartilage strips in ajoint. Tear can be the result of a traumatic injury, such as a twist,but also of mild and prolonged stresses, in which case it can also becalled degenerative tear. Tear are also referred to as ligamentsruptures.

“Treating,” or “Treatment,” as used herein, includes any administrationor application of a therapeutic for the disclosed diseases, disordersand conditions in subject, and includes inhibiting the progression ofthe disease, slowing the disease or its progression, arresting itsdevelopment, partially or fully relieving the disease, or partially orfully relieving one or more symptoms of a disease.

“Preventing” or “Prevention” as used herein, includes delaying orstopping the onset of disease, disorder, or condition.

Compositions

The invention comprises mesenchymal stem cell (MSCs) isolated from mixedcell populations with anti-integrin α10 antibodies. Therapeuticallyeffective amounts of isolated MSCs may be administered to treatdiseases/disorders like osteoarthritis, cartilage damage includingfissuring, and subchondral bone sclerosis.

The invention comprises an enriched integrin α10^(high) population ofMSCs wherein the cells are induced to express integrin α10 subunit andwherein the enriched integrin α10^(high) population of MSCs is apopulation wherein the percentage of MSCs expressing an integrin α10subunit is at least 60% of the cells of the population.

In some embodiments at least 65%, such as at least 70%, such as at least75%, such as at least 80%, such as at least 85%, such as at least 90%,such as at least 95%, such as at least 98%, such as at least 99%, suchas at least 100% of the total cells comprised in the enriched integrinα10^(high) population of MSCs express integrin α10 subunit.

In some embodiments the cells in the population of MSCs are induced toexpress integrin α10 subunit.

In some embodiments the integrin α10 is expressed as a heterodimer incombination with an integrin β1 subunit.

In some embodiments, the population of MSCs is derived from adiposetissue, bone marrow, synovial membrane, peripheral blood, cord blood,umbilical cord blood, Wharton's jelly, or amniotic fluid. Preferably, insome embodiments, the population of MSCs is derived from adipose tissue.Preferably, in some embodiments, the population of MSCs is derived frombone marrow.

In some instances, the enriched integrin α10^(high) population of MSCsis cultured in a plastic culture dish and induced to express integrinα10.

In some embodiments, the cells are cultured in a culture mediacomprising mammalian serum and FGF-2. In some embodiments, the cells arecultured in a culture media comprising platelet lysate and/or plateletlysate components. The term “platelet lysate components” refers to acomposition comprising only some of the elements that are usually foundin platelet lysate. For example, specific growth factor may be selectedor de-selected. In some embodiments, the cells are cultured in a culturemedia comprising FGF-2 and platelet lysate and/or platelet lysatecomponents. In some embodiments, the cells are cultured in a culturemedia comprising mammalian serum and platelet lysate and/or plateletlysate components. In some embodiments, the cells are cultured in aculture media comprising TGFβ. In some embodiments the cells arecultured in a serum-free culture media. In some embodiments the cellsare cultured in a serum-free culture media comprising platelet lysateand/or platelet lysate components. In some embodiments the cells arecultured in a serum-free culture media comprising growth factors, forexample FGF-2 and/or TGFβ. In some embodiments the cells are cultured ina culture media comprising mammalian serum, and the mammalian serum isfetal bovine serum. The examples of culture media herein above are allsuitable for inducing the cells to express integrin α10. However, otherculture media suitable for inducing the cells to express integrin α10exist and are known to the person skilled in the art.

In some embodiments, the enriched integrin α10^(high) population of MSCsis an in vitro cell culture.

In some embodiments, the cells are cultured in a culture media thatfurther comprises ascorbic acid.

In some embodiments, the cells are stored in a culture media thatfurther comprises dimethyl sulfoxide (DMSO). DMSO may be present in theculture media for storage purposes in volume comprised between 0 and 12%of the total culture volume, preferably at least 1%, such as at least2%, for example at least 3%, preferably at least 4%, such as at least5%, for example at least 6%, preferably at least 7%, such as at least8%, for example at least 9%, preferably at least 10% of the totalculture volume. DMSO is beneficial for storage of cells because itfacilitates freezing and thawing of the cell culture so that the cellscan be directly administered to the subject in need after thawing. DMSOmay also be eliminated after thawing by washing the cells.

In some embodiments DMSO facilitates the preventive or treating actionof the MSCs by reducing soft tissue swelling, inflammation, and edemasecondary to acute trauma, increased blood flow and promote vasculardilation

In some embodiments, the invention comprises a MSCs that expressesintegrin α10, CD44, CD90, and CD105, and lacks MHCII and CD45.

In some embodiments, the population of MSCs is derived from fetal,neonatal, juvenile or adult MSCs and/or progenitor cells.

In some embodiments, the population of MSCs are not derived fromembryonic cells or from an embryo.

In some embodiments, the invention comprises an in vitro cell culturecomprising undifferentiated MSCs expressing an integrin α10 subunit.

In some embodiments, the cells are derived from adipose or bone marrowtissue. In some embodiments, the cells in the culture have the capacityto differentiate into chondrocytes. In some embodiments, the cellculture comprises at least 1%, at least 2%, at least 3%, at least 4%, atleast 5%, at least 6%, at least 7%, at least 8%, at least 9%, at least10%, at least 20%, at least 30%, at least 40%, at least 50%, at least60%, at least 70%, at least 80%, or at least 90% chondrocytes afterdifferentiation. In some embodiments, the cells divide in a culturemedium containing serum and at least one proliferation-inducing growthfactor. In some embodiments, cells in the culture differentiate intochondrocytes upon withdrawal of both serum and the proliferationinducing growth factor. In some embodiments, the at least oneproliferation-inducing growth factor is selected from a group consistingof fibroblast growth factor (FGF)-2 or platelet lysate or combinationsthereof.

In some embodiments, the invention comprises a population of MSCs in aculture dish, wherein the cells had or previously had contact with mediacontaining an ingredient that induces expression of integrin α10, andwherein the percentage of integrin α10 positive cells comprises at least10%, at least 20%, at least 30%, at least 40%, at least 50%, at least60%, at least 70%, at least 80%, at least 90%, or at least 95% of thetotal cells. Preferably, the percentage of integrin α10 positive cellscomprised in the enriched integrin α10^(high) population comprises atleast 60%, at least 65%, at least 70%, at least 75%, at least 80%, atleast 85%, at least 90%, at least 95%, at least 98% or 100% of the totalcells.

In some embodiments, the invention comprises MSCs in a suspensionculture, wherein the cells express an integrin α10 subunit or anintegrin α10 polypeptide.

In some embodiments, the cells in suspension are substantially formedinto cell aggregates. For example, the aggregates may be in the form ofpellets or spheroids. In some embodiments, the cell aggregates aremaintained in a culture medium containing a proliferation-inducinggrowth factor.

In some embodiments, the enriched integrin α10^(high) population of MSCsfurther expresses at least one of CD44, CD90 or CD105. In someembodiments, the enriched integrin α10^(high) population of MSCs furtherexpresses both of CD44, CD90 and/or CD105. In some embodiments, theenriched integrin α10^(high) population of MSCs does not express MHCIIor CD45.

In some embodiments, the cells in the culture are human, murine, canineor equine. In some embodiments, the cells in the culture are human. Insome embodiments, the cells in the culture are equine. In someembodiments, the cells in the culture are canine.

In some embodiments, the cells in the enriched integrin α10^(high)population are selected from the group consisting of a mesenchymal stemcell, a mesenchymal progenitor cell, and a mesenchymal stromal cell.

In some embodiments, the cells in the enriched integrin α10^(high)population are derived from human fetal, neonatal, juvenile or humanadult MSCs. In some embodiments, the cells in the culture are notderived from human embryonic cells or from a human embryo.

In some embodiments, MSCs are cultured to expand in numbers and induceexpression of integrin α10.

In some embodiments, MSCs adhere to plastic culture dish. In someembodiments, non-adherent cells are discarded.

In some embodiments, integrin α10 expression is induced by addition ofdefined media. In some embodiments, this defined media is DMEMsupplemented with fetal bovine serum and FGF-2; DMEM supplemented withplatelet lysate; or commercially-available chemically defined media withfactors that perform the same function as FGF-2 or platelet lysate. Insome embodiments the enriched integrin α10^(high) population of MSCs iscultured in a culture media that comprises DMEM/F12, PRIME-XV®MSCExpansion SFM or STEMMACS.

In some embodiments, cells that express integrin α10 are isolated withan anti-integrin α10 antibody. For example, the anti-integrin α10antibody may be a monoclonal antibody. In some embodiments, the antibodyis produced by immunizing mice with a human integrin α10 polypeptide. Insome embodiments, cells that do not express integrin α10 are discarded.

In some embodiments the in vitro cell culture enriched for integrin α10expressing MSCs or the MSCs expressing integrin α10 isolated from the invitro cell culture are frozen and stored in closed plastic vials madeof, for example, cyclic olefin copolymer (COC) or any equivalentmaterial. Prior to administration to a subject in need thereof, thefrozen cells are thawed and can be administered without furthertreatment, or after washing.

In some embodiments, the population of MSCs is formulated into a cellaggregate prior to administration, usually even prior to freezing. Thecell aggregate may be in the form of a spheroid or of a pellet. It isadvantageous to administer the cells in aggregate form because they willhave a better homing capacity and they better mimic cartilage.

In some embodiments the in vitro cell culture enriched for integrin α10expressing MSCs or the MSCs expressing integrin α10 isolated from the invitro cell culture are used as a somatic cell therapy medicinal productor as a tissue engineered product.

Methods of Treatment

The present disclosure relates to methods for preventing and/or treatingsubchondral bone sclerosis and/or osteochondral damage comprisingadministering to the subject in need an enriched integrin α10^(high)population of MSCs.

The present disclosure relates to methods for preventing and/or treatingdegenerative joint disease (DJD), traumatic joint injuries, and/ordegenerative disc disease comprising administering to the subject inneed an enriched integrin α10^(high) population of MSCs.

In some embodiments the DJD is selected from a group consisting ofsubchondral bone sclerosis, subchondral bone disease, cartilagedegeneration, post-traumatic osteoarthritis, inflammatory arthritis, andcongenital malformation and/or deformation of the musculoskeletalsystem.

In some embodiments the traumatic joint injury comprises sport injuries.

In some embodiments the traumatic joint injury is selected from a groupconsisting of osteochondral damage, tendon damage, ligament damage, andmuscle damage.

In some embodiments, the osteochondral damage comprises articularcartilage damage and/or bone damage.

In some embodiments, the methods of the present disclosure may be usedfor treatment or prevention of arthritis.

The enriched integrin α10^(high) population of MSCs used in the methodsdisclosed herein is described in detail in the section above“Compositions”.

One of the advantages of the methods disclosed herein is that theenriched integrin α10^(high) population of MSCs, thanks to the integrinα10 expression, can effectively as high adherence and can easily attachto the damaged bone or cartilage.

In some embodiments, the methods of preventing subchondral bonesclerosis and/or osteochondral damage as disclosed herein compriseadministering the MSCs cells induced to express integrin α10 shortlyafter an injury to a joint has occurred, for example the same day,within one week, within two weeks, within three weeks, within one month,within two months, within 3 months, or within less than one year fromthe day of the injury. The administered MSCs can for example repair theinitial damage in bone and cartilage thus preventing or minimizing thedevelopment of subchondral bone sclerosis and progressive cartilagedegradation, which might otherwise develop into osteoarthritis. In fact,as a progressive degenerative joint disorder, osteoarthritis ischaracterized by cartilage damage, changes in the subchondral bone,osteophyte formation, muscle weakness, and inflammation of the synoviumtissue and tendon. Although osteoarthritis has long been viewed as aprimary disorder of articular cartilage, subchondral bone is attractingincreasing attention. It is commonly reported to play a vital role inthe pathogenesis of osteoarthritis. Subchondral bone sclerosis, togetherwith progressive cartilage degradation, is widely considered as ahallmark of osteoarthritis (Guangyi Li, Jimin Yin, Junjie Gao, Tak SCheng, Nathan J Pavlos, Changqing Zhang, and Ming H Zheng; Subchondralbone in osteoarthritis: insight into risk factors and microstructuralchanges; Arthritis Res Ther. 2013; 15(6): 223; and Castañeda S,Roman-Blas J A, Largo R, Herrero-Beaumont G; Subchondral bone as a keytarget for osteoarthritis treatment; Biochem Pharmacol. 2012 Feb. 1;83(3):315-23). Moreover osteochondral lesions or osteochondritisdessicans can occur in any joint, but are most common in the knee andankle. Such lesions are a tear or fracture in the cartilage covering oneof the bones in a joint. The cartilage can be torn, crushed or damagedand, in rare cases, a cyst can form in the cartilage. The presentdisclosure provides methods for treating subchondral bone sclerosis,hence the same methods may be used for successfully preventingosteoarthritis.

In some embodiments, the methods of treating subchondral bone sclerosisand/or osteochondral damage as disclosed herein comprise administeringthe MSCs cells induced to express integrin α10 to a subject diagnosedwith subchondral bone sclerosis and/or osteochondral damage. Theadministered MSCs cells induced to express integrin α10 can decrease athickening in the subchondral layer of a joint and/or decrease anincrease in bone density in a joint, thereby treating subchondral bonesclerosis and/or osteochondral damage.

An “osteochondral damage or injury” as used herein is an injury to thesmooth surface on the end of bones, called articular cartilage(chondro), and also to the bone (osteo) underneath it. The degree ofinjury ranges from a small crack to a piece of the bone breaking offinside the joint. These fragments can be of many sizes and depths andcan stay attached (stable) to the area that was injured or become loose(unstable) inside the joint. This injury is more common in adolescentsand young adults and typically occurs at the knee, ankle or elbow. Inparticular, recognised sites of osteochondral defects are:femoralcondyle (most common); humeral head; talus; and capitellum of thehumerus. It is a term that encompasses osteochondritis dissecans and isused synonymously with osteochondral damage or injury.

In some embodiments, the method comprises treating osteoarthritis in asubject comprising administering an enriched integrin α10^(high)population of MSCs or an MSC that has been isolated from a population ofMSCs using an anti-integrin α10 antibody to a subject who has, or is atrisk for, osteoarthritis, thereby treating osteoarthritis.

In some embodiments, the method comprises delaying or preventing theprogression of osteoarthritis in a subject comprising administering aenriched integrin α10^(high) population of MSCs that has been isolatedfrom a population of MSCs using an anti-integrin α10 antibody to asubject who has osteoarthritis, wherein the progression ofosteoarthritis is delayed as compared to a control who is notadministered the MSC.

In some embodiments, the method comprises treating subchondral bonesclerosis comprising administering an enriched integrin α10^(high)population of MSCs or an isolated MSC that has been isolated from apopulation of MSCs using an anti-integrin α10 antibody, thereby treatingsubchondral bone sclerosis.

In some embodiments, treating subchondral bone sclerosis comprisespreventing or reversing increase in bone formation around a joint. Insome embodiments, treating subchondral bone sclerosis comprisespreventing or decreasing a thickening in the subchondral layer of ajoint or preventing or decreasing an increase in bone density in ajoint.

In some embodiments, the method comprises treating a degenerative boneand joint disease comprising administering an enriched integrinα10^(high) population of MSCs or an isolated MSC that has been isolatedfrom a population of MSCs using an anti-integrin α10 antibody, therebytreating a degenerative bone and joint disease.

In some embodiments, the method comprises preventing a degenerative boneand joint disease comprising administering an enriched integrinα10^(high) population of MSCs or an isolated MSC that has been isolatedfrom a population of MSCs using an anti-integrin α10 antibody, therebypreventing a degenerative bone and joint disease.

In some embodiments, the subchondral bone sclerosis or osteochondraldamage is a degenerative joint disease or congenital malformation and/ordeformation of the musculoskeletal system.

In some embodiments, the subchondral bone sclerosis or osteochondraldamage is a degenerative joint disease selected from a group consistingof osteoarthritis, inflammatory arthritis, degenerative disk disease,sport injuries, traumatic joint injuries.

In some embodiments, the method comprises treating a sport injurycomprising administering an enriched integrin α10^(high) population ofMSCs or an isolated MSC that has been isolated from a population of MSCsusing an anti-integrin α10 antibody, thereby treating a sport injury.

In some embodiments, the method comprises treating a post-traumaticosteoarthritis

(PTOA) comprising administering an enriched integrin α10^(high)population of MSCs or an isolated MSC that has been isolated from apopulation of MSCs using an anti-integrin α10 antibody, thereby treatinga PTOA.

In some embodiments, the administering of the MSC compositions describedherein results in increased collagen production at the site ofadministration. In some embodiments, the administering of thecomposition results in increased type II collagen synthesis. In someembodiments, increased type II collagen synthesis is measured using aProCollagen II C-Propeptide Assay that measures the released carboxypropeptide in the formation of collagen, and therefore reflects changesin the rate of collagen type II synthesis. CPII tended to be greater insynovial fluid from treated limbs compared to control limbs. In someembodiments, the administering of the composition results in increasedproteoglycan production, and/or lubricin.

In some embodiments, a method of treating cartilage fissuring in asubject comprises administering an enriched integrin α10^(high)population of MSCs or a MSC that has been isolated from a population ofMSCs using an anti-integrin α10 antibody, thereby treating cartilagefissuring. In some embodiments, cartilage fissuring comprises cartilagefibrillation. In some embodiments, the cartilage fissure is in articularcartilage or cartilage at the end of bones. In some embodiments, thecartilage fissure occurs when there is cleavage within layers ofcartilage causing a separation between the layers. The cartilagefissuring may be an osteochondral damage, cartilage damage or injury.

In some embodiments, treating cartilage fissuring comprises a reductionin structural damage in the area of injury. In some embodiments,treating cartilage fissuring comprises preventing cartilage damage.

In some embodiments, MSCs are administered in the form of cellaggregates. In some embodiments, MSCs are administered as a pellet.Means to administer MSCs as pellets are known by those skilled in theart (see Bartz et al J. Transl Med. 14:317 (2016), hereby incorporatedby reference). In some embodiments, MSCs may be administered afterdifferentiation to chondrocytes as spheroids or as matrix-associatedchondrocyte implants. These administration forms result in easier homingof the cells into the damaged site.

In some embodiments, enriched integrin α10^(high) population of MSCs areadministered as a cell suspension. Pharmaceutically effective amounts ofMSCs are administered. MSCs may be administered together with apharmaceutically acceptable excipient.

In some embodiments, the enriched integrin α10^(high) population of MSCsare administered to a subject that has, or previously had, osteochondraldamage, cartilage damage or an injury to a joint or bone. In someembodiments, the osteochondral damage, cartilage damage or injury is abreak, sprain, bruise, or tear. For example, the damage may be cartilagefissure or ligament fibrillation. In some embodiments, the osteochondraldamage, cartilage damage or injury is a cartilage microfracture. In someembodiments, the osteochondral damage, cartilage damage or injury is achondral defect. In some embodiments, the osteochondral damage,cartilage damage or injury is the result of wearing a prosthesis. Forexample, the osteochondral damage, cartilage damage or injury in thejoint is in a muscle, tendon, bone, ligament, cartilage, or meniscus.

In some embodiments, the enriched integrin α10^(high) population of MSCsare administered to a subject having malalignment of a bone.

The enriched integrin α10^(high) population of MSCs may be administeredafter an injury to prevent the onset of disease. The enriched integrinα10^(high) population of MSCs may be administered after an injury duringa surgical repair of the injured joint and/or bone site. In someembodiment the enriched integrin α10^(high) population of MSCs isadministered at the same time as setting a bone after a break, forexample when repairing a fractured bone.

In some embodiments the enriched integrin α10^(high) population of MSCshas anti-inflammatory effect. Nevertheless, the enriched integrinα10^(high) population of MSCs may be administered at the same time as,before, or after the administration of another therapy, such as, forexample, an anti-inflammatory agent.

In some embodiment the enriched integrin α10^(high) population of MSCsmay be administered into a joint cavity. The enriched integrinα10^(high) population of MSCs may be administered via injection.

In some embodiment the enriched integrin α10^(high) population of MSCsis administered to a subject, wherein the subject is a human, horse,pony, ox, donkey, mule, camelid, cat, dog, pig, or cow. In preferredembodiments, the subject is human. In other preferred embodiment, thesubject is horse. In further preferred embodiments, the subject is dog.

In some embodiments, the administered enriched integrin α10^(high)population of MSCs are allogeneic or autologous. In some embodiment theenriched integrin α10^(high) population of MSCs and the subject are fromthe same species or genus. In some embodiment the enriched integrinα10^(high) population of MSCs and the subject are from a differentspecies or genus.

In some embodiments the in vitro cell culture enriched for integrin α10expressing MSCs or the MSCs expressing integrin α10 isolated from the invitro cell culture are administered as a somatic cell therapy medicinalproduct or as a tissue engineered product.

Methods of Manufacturing

One aspect of the present disclosure relates to a method ofmanufacturing the enriched integrin α10^(high) population of MSCs asdisclosed herein, the method comprising,

-   -   a. isolating a population of stem cells from adipose tissue,        bone marrow, synovial membrane, cord blood, Wharton's jelly, or        amniotic fluid;    -   b. culturing the isolated cells in a plastic culture vessel;    -   c. discarding non-adhered cells;    -   d. inducing integrin α10 expression by adding culture media,        wherein the culture media is a serum-free media or a media        comprising mammalian serum, and wherein the culture media        comprises platelet lysate and/or platelet lysate components,        and/or growth factors;    -   e. selecting the cells that express integrin α10, and    -   f. expanding the selected cells, thereby producing an enriched        integrin α10^(high) population of MSCs.

In some embodiments, the cells during induction of integrin α10expression are cultured in a culture media as described in the sectionabove “Composition”.

In some embodiments, the cells that express integrin α10 are selected instep e. using an anti-integrin α10 antibody, as described herein above.

In some embodiments, enriched integrin α10^(high) population of MSCsobtained is as described in the section above “Composition”.

In some embodiments, the cells are cultured in media that do notcomprise mammalian serum. For example, in some embodiments the cells arecultured in media that comprises or consists of platelet lysate orplatelet lysate components.

Items

-   1. An enriched integrin α10^(high) population of mesenchymal stem    cells (MSCs), wherein at least 60% of the cells of the population of    MSCs express integrin α10 subunit.-   2. The enriched integrin α10^(high) population of MSCs according to    item 1, wherein at least 65%, such as at least 70%, such as at least    75%, such as at least 80%, such as at least 85%, such as at least    90%, such as at least 95%, such as at least 96%, such as at least    97%, such as at least 98%, such as at least 99%, such as at least    100% of the total cells comprised in the population express integrin    α10 subunit.-   3. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are induced to    express integrin α10 subunit.-   4. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    culture media comprising mammalian serum and FGF-2.-   5. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    culture media comprising platelet lysate and/or platelet lysate    components.-   6. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    culture media comprising FGF-2 and platelet lysate and/or platelet    lysate components.-   7. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    culture media comprising mammalian serum and platelet lysate and/or    platelet lysate components.-   8. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    culture media comprising TGFβ.-   9. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    serum-free culture media comprising platelet lysate and/or platelet    lysate components.-   10. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    serum-free culture media comprising growth factors.-   11. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein the cells are cultured in a    serum-free culture media comprising the growth factors FGF2 and/or    TGFβ.-   12. The enriched integrin α10^(high) population of MSCs according to    any one of the preceding items, wherein said population is an in    vitro cell culture.-   13. A MSC isolated from the population of any one of the preceding    items with an anti-integrin α10 antibody.-   14. An enriched integrin α10^(high) population of MSCs for use in a    method of prevention or treatment of degenerative joint disease    (DJD), traumatic joint injuries, and/or degenerative disc disease,    -   wherein at least 60% of the cells of the population of MSCs        express integrin α10 subunit, and    -   wherein said MSC is selected from the group consisting of a        mesenchymal stem cell, a mesenchymal progenitor cell, and a        mesenchymal stromal cell.-   15. An enriched integrin α10^(high) population of MSCs for use in a    method of prevention or treatment of degenerative joint disease    (DJD), traumatic joint injuries, degenerative disc disease,    cartilage degeneration, subchondral bone sclerosis, post traumatic    osteoarthritis, inflammatory arthritis, subchondral bone disease,    sport injuries, osteochondral damage, articular cartilage damage,    bone damage, tendon damage, ligament damage and/or muscle damage,    -   wherein at least 60% of the cells of the population of MSCs        express integrin α10 subunit, and    -   wherein said MSC is selected from the group consisting of a        mesenchymal stem cell, a mesenchymal progenitor cell, and a        mesenchymal stromal cell.-   16. The enriched integrin α10^(high) population of MSCs for use    according to item 14, wherein DJD is selected from a group    consisting of subchondral bone sclerosis, subchondral bone disease,    cartilage degeneration, post-traumatic osteoarthritis, inflammatory    arthritis, and congenital malformation and/or deformation of the    musculoskeletal system.-   17. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 and 16, wherein the traumatic joint    injury comprises sport injuries.-   18. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 17, wherein the traumatic joint    injury is selected from a group consisting of osteochondral damage,    tendon damage, ligament damage, and muscle damage.-   19. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 and 18, wherein the osteochondral    damage comprises articular cartilage damage and/or bone damage.-   20. An enriched integrin α10^(high) population of MSCs for promoting    or inducing fracture healing, wherein at least 60% of the cells of    the population of MSCs express integrin α10 subunit, wherein said    MSC is selected from the group consisting of a mesenchymal stem    cell, a mesenchymal progenitor cell, and a mesenchymal stromal cell    .-   21. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 20, wherein at least 65%, such    as at least 70%, such as at least 75%, such as at least 80%, such as    at least 85%, such as at least 90%, such as at least 95%, such as at    least 96%, such as at least 97%, such as at least 98%, such as at    least 99%, such as at least 100% of the total cells comprised in the    population express integrin α10 subunit.-   22. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 21, wherein the cells are    induced to express integrin α10 subunit.-   23. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 22, wherein the cells are    cultured in a culture media comprising mammalian serum and FGF-2.-   24. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 23, wherein the cells are    cultured in a culture media comprising platelet lysate and/or    platelet lysate components.-   25. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 24, wherein the cells are    cultured in a serum-free culture media comprising platelet lysate    and/or platelet lysate components.-   26. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 25, wherein the cells are    cultured in a serum-free culture media comprising growth factors,    wherein the growth factors are FGF2 and/or TGFβ.-   27. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 26, wherein the cells are    cultured in a culture media comprising FGF-2 and platelet lysate    and/or platelet lysate components.-   28. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 27, wherein the cells are    cultured in a culture media comprising mammalian serum and platelet    lysate and/or platelet lysate components.-   29. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 28, wherein the cells are    cultured in a culture media comprising TGFβ.-   30. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 29, wherein said serum is fetal    bovine serum.-   31. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 30, wherein said population is    an in vitro cell culture.-   32. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 31, wherein said culture media    further comprises ascorbic acid.-   33. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 32, wherein said MSC is selected    from the group consisting of a mesenchymal stem cell, a mesenchymal    progenitor cell, and a mesenchymal stromal cell.-   34. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 33, wherein the integrin α10 is    expressed as a heterodimer in combination with an integrin β1    subunit.-   35. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 34, wherein the cells that    express integrin α10 are isolated with an anti-integrin α10    antibody.-   36. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 35, wherein the anti-integrin    α10 antibody is a monoclonal antibody.-   37. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 36, wherein the antibody is    produced by immunizing mice with a human integrin α10 polypeptide.-   38. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 37, wherein the MSCs are further    characterized by an absence of MHCII and CD45.-   39. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 38, wherein the MSCs are further    characterized by the presence of CD44, CD90 and CD105.-   40. The enriched integrin α10^(high) population of MSCs for use    according to anyone of items 14 to 39, wherein the cells are derived    from adipose tissue, bone marrow, synovial membrane, peripheral    blood, cord blood, umbilical cord blood, Wharton's jelly, or    amniotic fluid.-   41. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 40, wherein the cells are    derived from adipose tissue.-   42. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 41, wherein the cells are    derived from bone marrow.-   43. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 42, wherein the population is    for use in a method of prevention of subchondral bone disease and/or    osteochondral damage.-   44. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 43, wherein the population is    for use in a method of treatment of subchondral bone disease and/or    osteochondral damage.-   45. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 44, wherein the subject has, or    previously had, osteochondral damage, cartilage damage or an injury    to a joint or bone.-   46. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 45, wherein the osteochondral    damage, cartilage damage or injury is a break, sprain, bruise, tear,    fracture or rupture.-   47. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 46, wherein the osteochondral    damage, cartilage damage or injury is a cartilage fissure.-   48. The enriched integrin α10high population of MSCs for use    according to any one of items 14 to 47, wherein the osteochondral    damage, cartilage damage or injury is a cartilage microfracture.-   49. The enriched integrin α10high population of MSCs for use    according to any one of items 14 to 48, wherein the osteochondral    damage, cartilage damage or injury is a chondral defect.-   50. The enriched integrin α10high population of MSCs for use    according to any one of items 14 to 49, wherein the osteochondral    damage, cartilage damage or injury is a tendon rupture or a ligament    rupture.-   51. The enriched integrin α10high population of MSCs for use    according to any one of items 14 to 50, wherein the osteochondral    damage, cartilage damage or injury is a bone fracture.-   52. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 51, wherein the injury is a    sports injury.-   53. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 52, wherein the subject has    malalignment of a bone.-   54. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 53, wherein osteochondral    damage, cartilage damage or injury is the result of wearing a    prosthesis.-   55. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 54, wherein the osteochondral    damage, cartilage damage or injury in the joint is in a muscle,    tendon, bone, ligament, cartilage, or meniscus.-   56. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 55, wherein the method prevents    post-traumatic osteoarthritis (PTOA) resulting from subchondral bone    disease or osteochondral damage.-   57. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 56, wherein the MSCs are    allogeneic or autologous.-   58. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 57, wherein the MSCs are    administered into a joint cavity.-   59. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 58, wherein the population of    MSCs is administered via injection.-   60. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 59, wherein the population of    MSCs is administered in a cell suspension with a pharmaceutically    acceptable excipient.-   61. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 60 wherein the population of    MSCs is formulated into a cell aggregate prior to administration.-   62. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 61, wherein the population of    MSCs is administered during a surgery to repair a damaged joint    and/or bone.-   63. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 62, wherein the population of    MSCs is administered at the same time as setting a bone after a    break.-   64. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 63, wherein the subject is a    human, horse, pony, ox, donkey, mule, camelid, cat, dog, pig, or    cow.-   65. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 64, wherein the subject is    human.-   66. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 65, wherein the subject is    horse.-   67. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 66, wherein the subject is dog.-   68. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 67, wherein the MSCs and subject    are from the same species or genus.-   69. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 68, wherein the MSCs and subject    are from a different species or genus.-   70. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 69, wherein the cells are    derived from fetal, neonatal, juvenile or adult MSCs and/or    progenitor cells.-   71. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 70, wherein the cells are not    derived from embryonic cells or from an embryo.-   72. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 71, wherein the administration    results in increased collagen production, proteoglycan production,    and/or lubricin at the site of administration.-   73. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 72, further comprising    administering an anti-inflammatory agent in combination with the    MSCs.-   74. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 73, wherein the MSCs do not    express MHCII and CD45.-   75. The enriched integrin α10^(high) population of MSCs for use    according to any one of items 14 to 74, wherein the MSCs express    CD44, CD90 and CD105.-   76. Use of an enriched integrin grin α10^(high) population of MSCs,    wherein at least 60% of the total cells comprised in the population    express integrin α10 subunit, and wherein said MSC is selected from    the group consisting of a mesenchymal stem cell, a mesenchymal    progenitor cell, and a mesenchymal stromal cell, for the preparation    of a medicament for the prevention or treatment of degenerative    joint disease (DJD), traumatic joint injuries, and/or degenerative    disc disease.-   77. A method of treating and/or preventing a degenerative joint    disease (DJD), traumatic joint injuries, and/or a degenerative disc    disease in a subject comprising administering an enriched integrin    α10^(high) population of MSCs to a subject at risk for, or having,    subchondral bone sclerosis, wherein at least 60% of the cells of the    population of MSCs express integrin α10 subunit, and wherein said    MSC is selected from the group consisting of a mesenchymal stem    cell, a mesenchymal progenitor cell, and a mesenchymal stromal cell,    thereby treating and/or preventing a degenerative joint disease    (DJD), traumatic joint injuries, and/or a degenerative disc disease.-   78. The use or method according to any one of items 76 and 77,    wherein the DJD is selected from a group consisting of subchondral    bone sclerosis, subchondral bone disease, cartilage degeneration,    post-traumatic osteoarthritis, inflammatory arthritis, and    congenital malformation and/or deformation of the musculoskeletal    system.-   79. The use or method according of any one of items 76 to 78 wherein    the traumatic joint injury comprises sport injuries.-   80. The use or method according of any one of items 76 to 79 wherein    the traumatic joint injury is selected from a group consisting of    osteochondral damage, tendon damage, ligament damage, and muscle    damage.-   81. The use or method according of any one of items 76 to 80 wherein    the osteochondral damage comprises articular cartilage damage and/or    bone damage.-   82. The use or the method according to any one of items 76 to 81,    wherein at least 65%, such as at least 70%, such as at least 75%,    such as at least 80%, such as at least 85%, such as at least 90%,    such as at least 95%, such as at least 96%, such as at least 97%,    such as at least 98%, such as at least 99%, such as at least 100% of    the total cells comprised in the population express integrin α10    subunit.-   83. The use or the method according to any one of items 76 to 82,    wherein the cells are induced to express integrin α10 subunit.-   84. The use or the method according to any one of items 76 to 83,    wherein the stem cells are derived from adipose tissue, bone marrow,    synovial membrane, peripheral blood, cord blood, umbilical cord    blood, Wharton's jelly, or amniotic fluid.-   85. The use or the method according to any one of items 76 to 84,    wherein the MSCs are derived from adipose tissue.-   86. The use or the method according to any one of items 76 to 85,    wherein the MSCs are derived from bone marrow.-   87. The use or the method according to any one of items 76 to 86,    wherein the subject has, or previously had, osteochondral damage,    damage or an injury to a joint or bone.-   88. The use or the method according to any one of items 76 to 87,    wherein the osteochondral damage, cartilage damage or injury is a    break, sprain, bruise, tear, fracture or rupture.-   89. The use or the method according to any one of items 76 to 88,    wherein the osteochondral damage, cartilage damage or injury is a    cartilage microfracture.-   90. The use or the method according to any one of items 76 to 89,    wherein the osteochondral damage, cartilage damage or injury is a    chondral defect.-   91. The use or the method according to any one of items 76 to 90,    wherein the osteochondral damage, cartilage damage or injury is a    tendon rupture or a ligament rupture.-   92. The use or the method according to any one of items 76 to 91,    wherein the osteochondral damage, cartilage damage or injury is a    bone fracture.-   93. The use or the method according to any one of items 76 to 92,    wherein the injury is a sports injury.-   94. The use or the method according to any one of items 76 to 93,    wherein the subject has malalignment of a bone.-   95. The use or the method according to any one of items 76 to 94,    wherein the osteochondral damage, cartilage damage or injury is the    result of wearing a prosthesis.-   96. The use or the method according to any one of items 76 to 95,    wherein the osteochondral damage, cartilage damage or injury in the    joint is in a muscle, tendon, bone, ligament, cartilage, or    meniscus.-   97. The use or the method according to any one of items 76 to 96,    wherein the osteochondral damage, cartilage damage or injury is    cartilage fissuring.-   98. The use or the method according to any one of items 76 to 97,    wherein the use or method prevents post-traumatic osteoarthritis    (PTOA) resulting from subchondral bone disease or osteochondral    damage.-   99. The use or the method according to any one of items 76 to 98,    wherein the MSCs are allogeneic or autologous.-   100. The use or the method according to any one of items 76 to 99,    wherein the MSCs are administered into a joint cavity.-   101. The use or the method according to any one of items 76 to 100,    wherein the MSCs are administered via injection.-   102. The use or the method according to any one of items 76 to 101,    wherein the MSCs are administered in a cell suspension with a    pharmaceutically acceptable excipient.-   103. The use or the method according to any one of items 76 to 102,    wherein the MSCs are formulated into a cell aggregate prior to    administration.-   104. The use or the method according to any one of items 76 to 103,    wherein the MSCs are stored in a media comprising dimethyl sulfoxide    (DMSO).-   105. The use or the method according to any one of items 76 to 104,    wherein the MSCs are administered during a surgery to repair a    damaged joint or bone.-   106. The use or the method according to any one of items 76 to 105,    wherein the MSCs are administered at the same time as setting a bone    after a break.-   107. The use or the method according to any one of items 76 to 106,    wherein the subject is a human, horse, pony, ox, donkey, mule,    camelid, cat, dog, pig, or cow.-   108. The use or the method according to any one of items 76 to 107,    wherein the subject is human.-   109. The use or the method according to any one of items 76 to 108,    wherein the subject is horse.-   110. The use or the method according to any one of items 76 to 109,    wherein the subject is dog.-   111. The use or the method according to any one of items 76 to 110,    wherein the MSCs and subject are from the same species or genus.-   112. The use or the method according to any one of items 76 to 111,    wherein the MSCs and subject are from a different species or genus.-   113. The use or the method according to any one of items 76 to 112,    wherein the cells are derived from fetal, neonatal, juvenile, or    adult MSCs and/or progenitor cells.-   114. The use or the method according to any one of items 75 to 113,    wherein the cells are not derived from embryonic cells or from an    embryo.-   115. The use or the method according to any one of items 76 to 114,    wherein the administration results in increased collagen production,    proteoglycan production, and/or lubricin at the site of    administration.-   116. The use or the method according to any one of items 76 to 115,    further comprising administering an anti-inflammatory agent in    combination with the MSCs.-   117. The use or the method according to any one of items 76 to 116,    wherein the MSCs do not express MHCII and CD45.-   118. The use or the method according to any one of items 76 to 117,    wherein the MSCs express CD44, CD90 and CD105.-   119. A method of manufacturing the enriched integrin α10^(high)    population of MSCs according to any one of items 1 to 13, the method    comprising,    -   a. isolating a population of stem cells from adipose tissue,        bone marrow, synovial membrane, cord blood, Wharton's jelly, or        amniotic fluid;    -   b. culturing the isolated cells in a plastic culture vessel;    -   c. discarding non-adhered cells;    -   d. inducing integrin α10 expression by adding culture media,        wherein the culture media is a serum-free media or a media        comprising mammalian serum, and wherein the culture media        comprises platelet lysate and/or platelet lysate components,        and/or growth factors;    -   e. selecting the cells that express integrin α10, and    -   f. expanding the selected cells, thereby producing an enriched        integrin α10^(high) population of MSCs.-   120. The method according to item 119, wherein the culture media in    step d.

comprises the growth factors FGF2 and/or TGFβ.

EXAMPLES Example 1 Characterization of Equine MSCs

Equine MSCs were isolated from bone marrow (BM) and adipose tissue (AT).BM aspirates and neck adipose tissue were obtained from healthy equinecadavers with permit from the Swedish Board of Agriculture.

BM aspirates were washed in phosphate buffered saline (PBS) and platedonto cell-culture flasks for plastic adherence in DMEM-F12 media (Gibco)supplemented with 10% fetal bovine serum (FBS) (Biological Industries),50 μg/L fibroblast growth factor (FGF)-2 (Miltenyi) and 100 U/mLAntibiotic-Antimycotic (Gibco) and incubated at 37° C. in a humidifiedincubator with 4% O₂ and 5% CO₂. After 24 h, the non-adherent cells werediscarded and fresh medium added. At approximately 80% confluence cellswere passaged using Accutase (Gibco) and replated for expansion at adensity of 104 cells/cm² in DMEM F-12 media containing 5% human plateletlysate (PL) from Cook Regentec, 50 μg/L FGF-2 andAntibiotic-Antimycotic.

AT from the equine neck was aseptically minced into smaller pieces andwashed prior to digestion with 0.1% type 1 collagenase (Sigma-Aldrich)at 37° C. with gentle agitation for 1.5 h. The samples were centrifugedfor 5 min at 300×g where after the adipocyte layer and the collagenasesupernatant were aspirated. The remaining stromal vascular fraction waswashed with DMEM F-12 medium, filtered through a 100 μm cell strainerand seeded into cell culture flasks containing DMEM F-12 supplementedwith 10% FBS and Antibiotic-Antimycotic at a plating density ofapproximately 35 mL adipose tissue per 200 cm². Cells were incubated at37° C. in a humidified incubator with 4% O₂ and 5% CO₂ and after 24 h,the non-adherent cells were discarded and media containing DMEM F-12, 5%PL and Antibiotic-Antimycotic added. Medium was replaced every 2-3 dayand cells were harvested at 80% confluence using Accutase and reseededfor expansion at a cell density of 5000 cells/cm² in DMEM F-12 mediacontaining 5% PL, 50 μg/L FGF-2 and Antibiotic-Antimycotic.

At each passage the MSCs were immunophenotyped by flow cytometryanalysis using a panel of cell surface markers: integrin α10β1(Xintela), CD90 (BD Pharmingen), CD44, CD105, CD45 and MHC class II (AdBSerotec). In brief, 100,000 cells were washed in PBS supplemented with1% FBS and 0.1% sodium azide followed by incubation with selectiveantibody. After incubation, cells were washed twice in buffer andacquired using a BD Accuri C6 flow cytometer. At least 20,000 cells wereacquired and analyzed. Results are expressed as percentage of positivecells.

Cells were cultured under hypoxia with PL and FGF-2. MSCs are oftenroutinely propagated in medium containing FGF-2 in order to preserve astem-like phenotype. However, FGF-2 upregulates MHC II on MSCs inculture²¹. Therefore, cultures were initially supplemented with PL only.MSCs isolated from BM or AT and cultured in media containing plateletlysate exhibited good growth characteristics with doubling times of 1.9days (46 hours) and 1.6 days (38 hours) respectively. Both AT and BMderived cells showed a morphology typical for MSCs.

Cells were continuously monitored for expression of integrin α10, CD44,CD45, CD90 and CD105 by flow cytometry. MSCs expressed high levels ofthe markers CD44, CD90 and CD105 and lacked the hematopoietic cellmarker CD45 and MHC class II (HLA-DR) (FIG. 1 ).

For human MSCs, the cell phenotypes plastic adherence and expression ofthe surface markers CD73, CD90, and CD105 as well as absence of CD45,CD34, CD14 or CD11b, CD79a or CD19 and HLA-DR surface molecules meetsthe minimal surface antigen criteria for MSC definition⁹. Due to lack ofvalidated antibodies reacting with equine cell surface markers,expression of CD73, CD34, CD14 or CD11 b, CD79α or CD19 were notevaluated. However, both AT- and BM-derived cells adhered to plastic,expressed the tested MSC markers, did not express CD45 or MHC class IIand differentiated into chondrocytes.

Conclusion: AT- and BM-derived cells expressing integrin α10 adhered toplastic, expressed the tested MSC markers (CD44, CD90, and CD105), didnot express CD45 or MHC class II and differentiated into chondrocytes.

Example 2 Differentiation of MSCs into Chondrocytes

According to literature, equine MSCs have difficulties differentiatinginto chondrocytes¹⁶⁻¹⁸. However, studies with human AT- MSCs show thatthis could be due to lack of TGFβ-receptors and thus unresponsiveness tothe chondrogenic induction signal TGFβ1⁹. This deficiency can beovercome by adding BMP-6 which will stimulate TGFβ-receptor expressionin human AT derived MSCs²⁰. Integrin α10 expression is up-regulated onhuman FGF-2-treated MSCs with subsequent improved chondrogenicdifferentiation potential¹⁵. Equine AT derived MSCs were primed forchondrogenic differentiation in normal cell culture in fetal bovineserum containing medium and in a medium containing FGF-2. Chondrogenicdifferentiation was also compared by collagen type II expression inpellet mass cultures after 28 days of incubation in media containing noadded growth factors, TGFβ3 only or TGFβ3 and BMP-6 in two differentconcentrations. Chondrogenic differentiation of equine BM derived MSCswas used for comparison.

Equine AT derived MSCs were cultured and expanded to passage 3 beforebeing subjected to integrin α10 fluorescence-activated cell sorting byFACSAria (BD). The cells were stained using a monoclonal anti-integrinα10 (Xintela) and live cells were sorted into two populations: integrinα10 positive and integrin α10 negative cells. Discrimination oflive/dead cells was accompanied by 7-AAD staining (BioLegend). Sortedcells were washed in medium and re-seeded for recovery and expansion onepassage before chondrogenic differentiation experiments were performed.To determine the chondrogenic differentiation capacity of non-sorted andintegrin α10 sorted cells, 200,000 MSCs at passage 4 were pelleted in 15mL polypropylene tubes with chondrogenic medium consisting of DMEM with4.5 g glucose/L (Gibco) supplemented with 20 μg/L TGFβ3, 20 μg/L BMP-6,50 mg/L L-ascorbic acid-2-phosphate, 1% Insulin-Transferrin-Selenium(ITS) and 100 nM dexamethasone (Sigma Aldrich). Various growth factorconcentrations and combinations of these were tested to optimize equineAT derived MSC chondrogenic differentiation conditions. Medium waschanged three times per week and generally maintained for 28 days or asindicated in the chondrogenic time study. Pellets were either embeddedin Optimal Cutting Temperature compound (HistoLab) for cryosectioning orsnap frozen and stored at −80° C. for RNA extraction. Non-inducedchondrogenic pellet mass cultures were used as negative controls in thesubsequent immunohistology stainings and PCR experiments.

The pellets were cryosectioned and stained with Alcian Blue fordetection of proteoglycans or subjected to immunohistochemical analysisusing antibodies directed to the cartilage specific protein collagentype II (Ab3092, Abcam) and integrin α10 (Xintela).

Conclusion: AT- and BM-derived equine MSCs differentiate intochondrocytes.

Example 3 Levels of Integrin α10 Expression Correlate with ChondrogenicDifferentiation Potential

Expression of integrin α10β1 on equine MSCs derived from AT and BM wasexamined. Equine AT derived MSCs were cultured and expanded to passage 3before being subjected to integrin α10 fluorescence-activated cellsorting by FACSAria (BD). The cells were stained using a monoclonalanti-integrin α10β1 (Xintela) and live cells were sorted into twopopulations: integrin α10 positive and integrin α10 negative cells.

Discrimination of live/dead cells were accompanied by 7-AAD staining(BioLegend). Sorted cells were washed in medium and re-seeded forrecovery and expansion one passage before chondrogenic differentiationexperiments were performed.

Flow cytometry analysis of integrin α10 expression revealed thatintegrin α10 expression was significantly higher in BM derived MSCscompared to AT derived MSCs. Almost 100% of the BM derived MSCs wereintegrin α10 positive, compared to approximately 30% of the AT derivedMSCs (FIG. 2A-B).

To examine the importance of integrin α10 for chondrogenicdifferentiation, AT derived MSCs were sorted into two distinct cellpopulations by fluorescence activated cell sorting (FACSAria) usingspecific monoclonal antibodies (mAbs) (FIG. 3A). All integrin α10^(high)MSCs expressed integrin α10β1 and expression was localized to the cellsurface as shown by immunofluorescence staining (FIG. 3B). The two cellpopulations, integrin α10 enriched (α10^(high)) and α10 depleted(α10^(low)), were then expanded and used in pellet mass cultures, wherethey were compared to unsorted cells. Cells from four equine donors wereused. Sorted cells were transferred to pellet mass cultures,differentiated for 28 days, sectioned and analyzed byimmunohistochemistry. Immunohistochemical analysis of pelletcryosections showed strong labeling of collagen type II in the pelletsmade with integrin α10^(high) cells while collagen type II was lower inthe integrin α10^(low) pellets (FIGS. 4A-D). Gene expression analysis ofpellet mass cultures was made with RNA from unsorted and sorted((α10^(high)) or ((α10^(low))) AT derived MSCs. GAPDH was used asendogenous control and unsorted cells were used as reference sample forΔΔCt calculation. Total RNA was extracted by homogenization of pelletsin QIAzol using Precellys lysing kit beads and “homogenisator” followedby RNA isolation according to the RNeasy Lipid Tissue Mini kit (QIAGEN).The RNA was reverse-transcribed into cDNA using a SuperScript VILO kit(Invitrogen). Real-time PCR was conducted using TaqMan assays for thefollowing equine gene transcripts: ACAN, COL1A1, COL2A1, GAPDH, RUNX2,and SOX9 together with the TaqMan Universal Master Mix II according tothe protocol in a StepOne Plus Real Time PCR System device (AppliedBiosystems). The relative mRNA expression was calculated using the2^(ΔΔCt) method where GAPDH was the endogenous control (ΔCt) andnormalized towards unsorted cells (ΔΔCt)

Conclusion: The gene expression results show higher expression of typeII collagen and aggrecan in integrin α10^(high) pellets compared tointegrin 10^(low) pellets, indicating better chondrogenicdifferentiation in the pellets from integrin α10^(high) sorted cells(FIG. 5 ).

Example 4 Levels of Integrin α10 Expression Correlate with HomingPotential

To determine the homing capacity of non-sorted and integrin α10 sortedcells to intact or damaged cartilage, MSCs were incubated for 1 h inrotating plastic tubes with bovine osteochondral explants. Theseexplants were wounded in two locations. One exposing subchondral boneand one with a shallower wound only exposing cartilage. After 1 hadherent cells were counted (with Image J counting cells-plugin)separately for undamaged regions, chondral defects and subchondraldefects. Results from two independent experiments are shown in FIG. 6 .Integrin α10^(high) cells bound better overall (FIG. 6A), and boundbetter to intact cartilage (FIG. 6B), chondral defects (FIG. 6C), andsubchondral defects (FIG. 6D) than unsorted cells or integrin α10^(low)cells.

Conclusion: This shows that cells expressing higher levels of integrinα10 (α10high cells) could be better at homing to the region of interestfor cartilage repair.

Example 5 Investigation of Integrin α10β1 Positive MSCs in Horses withPost Traumatic Osteoarthritis (PTOA)

This study evaluated the safety and efficacy of integrin α10β1 positiveMSCs in an equine PTOA model.

A. Animals and Surgeries

Horses were selected for inclusion in the study based on age (range, 2-5years). Prior to enrolment, each horse underwent a routine generalphysical examination and a lameness evaluation to rule out body systemabnormalities, particularly musculoskeletal and neurologicabnormalities, which could impact the study. Only horses determined tobe sound in the hind limbs and in good general health were enrolled inthe study.

Upon arrival, horses were confined to stalls. Clinical parameters wereevaluated once pre-operatively, twice daily for 3 days post-operatively,then once daily for 10 days post-operatively. Daily physical examsincluded vital parameters, mucous membrane color, capillary refill time,gastrointestinal motility, digital pulses, fecal and urine output,appetite, and water intake. Physical exam values were recorded in eachhorse's individual medical record. Anesthesia was induced, maintained,and monitored, by board certified veterinary Anesthesiologists. Horseswere sedated, and then general anesthesia was induced and maintainedaccording to the discretion of the anesthesiologist and in agreementwith the study and IACUC protocols. Additional medication or fluidtherapy was administered when necessary, at the discretion of theattending anesthesiologist. Following completion of the surgicalprocedure, horses were placed in lateral recumbency in a padded recoverybox. Horses were given additional sedation for recovery. Theendotracheal tube was removed once the horse was breathingspontaneously. Horses were monitored continuously during anestheticrecovery and returned to their stall once standing steadily and fullyloading all limbs. No significant complications were encountered duringinduction, general anesthesia, or anesthetic recovery. Anesthetizedhorses were positioned in dorsal recumbency and both left and right hockjoints were clipped. Aseptic preparation of the skin and routine steriledraping were then performed. A standard dorsal approach was made to thehock (talocrural) joint. An 18-gauge needle was placed in the joint andsynovial fluid was collected for analysis, as described below. The jointwas distended with saline. A 5 mm stab incision was made lateral to theextensor tendon, and the arthroscope was inserted. The joint wasexplored and needles were used to determine the portal position forintroduction of the impactor. The impactor was positioned within thejoint so that the tip was perpendicular to the axial surface of themedial trochlear ridge of the talus. Three impacts, spaced approximately1 cm apart, were applied to the axial aspect of the medial trochlearridge of the talus. Impact force was recorded during impact by a loadcell within the impactor. A synovial membrane biopsy was obtained forhistologic analysis. This procedure was repeated on the opposite limb.Arthroscopic video was obtained of all surgeries. The skin incisionswere closed using non-absorbable suture material in simple interruptedpattern, the joints were bandaged, and the horse was transported torecovery.

B. Preparation and Injection of Equine Inteqrin Alpha 10 Selected MSCs

Cells prepared according to Examples 1-3, called Equine integrin alpha10selected MSCs, hereinafter “Eq12a10+0.1 cells”, were utilized in thesestudies. Eq12a10+0.1 cells were stored in liquid nitrogen until use(four-days post-impact surgery). Vials were thawed, cells were counted,and the viability was assessed using trypan blue. The cells were thencentrifuged and resuspended in PBS at a concentration of approximately6×10⁶ cells/ml. Cells were immediately transferred to the treatment areafor injection.

Three ml aliquots of both the cell suspension and control PBS wassterilely drawn into 6 ml syringes through 3-inch, 18-gauge needles.Cells were aspirated slowly, over 20-30 seconds. To prepare forinjection, the horse was chemically and physically restrained asnecessary, and the dorsomedial pouch of the talocrural joint wasaseptically prepped bilaterally. The randomized limb receiving the testarticle was injected first; a 19-gauge needle was inserted into thedorsomedial compartment of the talocrural joint, synovial fluid wasaspirated into a 3-ml syringe, and then the loaded syringe was attachedand the solution was emptied at a slow and steady pace (over 3-5seconds) to deliver more than 1 million cells into the joint cavity. Thesame procedure was followed for injection of the control PBS into theopposite limb.

Preoperative preparation and anesthesia were carried out as describedabove for the initial surgeries. Anesthetized horses were positioned indorsal recumbency and both left and right hock joints were clipped,prepped and draped routinely. A standard dorsal lateral approach wasmade to the hock joint. An 18-gauge needle was placed in the talocruraljoint and synovial fluid was collected for analysis, as described below.The joint was distended with saline. A 5 mm stab incision was madelateral to the extensor tendons for the arthroscopic sleeve. The jointwas explored and scored using the ICRS scoring method. A synovialmembrane biopsy was obtained for histologic analysis. This procedure wasrepeated on the opposite limb. The skin incisions were closed usingnon-absorbable suture material in simple interrupted pattern, the hockjoints were bandaged, and the horse was transported to recovery.Post-operative recovery was as described above.

Synovial fluid samples from each talocrural joint were aspirated fromall horses immediately prior to the impact surgery and at days 4, 7, 14,28, 42, 70, 98, 126, 154 post-operatively as well as at euthanasia. Attime points other than that of the impact surgery, the test articleinjection, and the 6 week recheck surgery, horses were chemically andphysically restrained as necessary and the dorsomedial pouches of thetalocrural joints were aseptically prepped bilaterally. A 19-gaugeneedle was inserted into the dorsomedial compartment of the talocruraljoint and synovial fluid was aspirated into a 3-mL syringe.Approximately 1 mL of the aspirate was submitted to the CornellUniversity Clinical Pathology Laboratory for a full synovial fluidevaluation (smear and differential counts). The remaining synovial fluidsamples were centrifuged to remove the cell pellet, transferred intomicrocentrifuge tubes and stored in a −80° C. freezer.

At 6 months, horses were sedated and humanely euthanized according toAVMA guidelines with an intravenous overdose of barbiturate(pentobarbital). Joint fluid was collected by sterile methods, and astandard necropsy examination was performed by a board certifiedveterinary pathologist. Tissue samples of the major organs werecollected for histologic examination. Talocrural joints were harvested,tagged for identification and packaged for transport in a cooler. Chainof custody forms remained with the joints at all times.

C. Analyses

Following MRI examination, talocrural joints were dissected andexamined. Samples of the synovial membrane were harvested and fixed forhistologic processing. India ink was applied to the articular surface,and digital photographs were obtained. India ink contains particulatecarbon, and adheres to area of the articular surface where the cartilageintegrity is compromised. Osteochondral blocks containing the impactsites as well as non-impacted control cartilage were harvested and fixedfor histologic processing.

For each outcome measure of joint health with more than one samplingtime (lameness, synovial fluid analysis, synovial fluid ELISA,arthroscopic scores, synovial membrane histology) a mixed effect modelwas fitted to the data with horse as a random effect, and treatment(control or treatment) and time as fixed effects and an interaction termfor treatment*time. Tukey's post hoc and linear contrasts were used asappropriate to test differences between groups of specific interest. Apaired t-test was performed on cartilage histology and MRI scores.Statistical analysis was performed using JMP 12 (SAS Institute, Cary,N.C., USA). Significance was set at p<0.05.

Model fit for the majority of analyses was fair (adjusted R²=0.25−0.50)or good (R²=0.50−0.75), which are considered acceptable for in vivoanimal studies. Model fit was poor (adjusted R²=<0.25) in someinstances.

D. Radiograph Results

Summary radiograph data are presented in Table 5.

Baseline (pre-operative) findings: On pre-operative radiographs, all butone horse had radiographically normal hock joints; free of sclerosis,periarticular osteophytes, joint space narrowing, or joint enlargement.One horse had a mild periarticular osteophyte on the dorsomedial surfaceof the proximal central tarsal bone. This was documented and determinedto be inconsequential for study inclusion criteria.

Subchondral bone sclerosis: At the 6-month study end, the control grouphad significantly more sclerosis than the treatment group (FIG. 7 ;p=0.004; adjusted R²=0.03). Sclerosis is increased bone density whichmakes the bone harder and less able to absorb and transmit forces awayfrom the articular cartilage. Sclerosis is a hallmark of osteoarthritisand can be either a cause or a result of cartilage deterioration.Because this study is a model system for post-traumatic osteoarthritis,it follows that the increase in subchondral bone sclerosis is a resultof joint trauma, verifying that this model induces osteoarthritis. Theincrease in sclerosis in the control group at study end suggests thatthe cartilage in the control group would continue to deteriorate overtime due to the increased absorption of forces transmitted during weightbearing.

Conclusion: at the 6-month study endpoint, less radiographic subchondralbone sclerosis was found in the treated limbs compared to controls.Subchondral bone sclerosis would likely result in continued cartilagedeterioration and progression of arthritis, and this effect would beexpected to be magnified in the face of exercise.

E. Synovial Fluid ELISA Results

Six ELISAs were performed on synovial fluid samples that were obtainedfrom the left and right talocrural joints at time points 0, 4, 7, 14,28, 42, 70, 98, 126, 154, and 169 days post-operatively. Samples werecentrifuged to remove cell debris and stored at −80° C. until analysis.Summary data is presented below in Table 9.

Prostaglandin E2 (PGE-2): MSCs are thought to be immunomodulatory,partially thought upregulation of PGE-2. PGE-2 increased in bothtreatment and control groups from time 0 to 28 days. It then sharplydecreased and remained low, but higher than baseline values throughoutthe study. PGE-2 concentration was higher in treatment compared tocontrol limbs at 9 of the 11 time points. At 28 days, PGE-2 wassignificantly increased in treated limbs compared to control at time 0,4, 42, 56, 126, and 154 days (FIG. 8 ), suggesting enhanced modulationof the post-operative articular environment in treated compared tocontrol limbs.

Collagen CPII: This assay is also known as ProCollagen II C-PropeptideAssay. The CPII assay measures the released carboxy propeptide in theformation of collagen, and therefore reflects changes in the rate ofcollagen type II synthesis. CPII tended to be greater in synovial fluidfrom treated limbs compared to control limbs (FIG. 9 ) suggestingincreased type II collagen synthesis in the treated limbs. Both treatedand control limbs had increased CPII at 7 and 14 days post-operativelycompared to time zero and study end.

Collagen C2C: This assay measures the neoepitope (at C-terminus of ¾peptide) generated through cleavage of type-II collagen by collagenases.C2C concentrations significantly increased in treated and control jointsat days 4-14 post operatively (FIG. 10 ), and then decreased throughoutthe study to values not significantly different from time 0. Like TNF-α,this support the model as one of mild post-traumatic osteoarthritis.

F. Cartilage Histology Results

All H&E and Safranin-O fast green stained osteochondral slides werescored by consensus of investigators, who were blinded to treatmentgroup while scoring. Data are presented in FIG. 11 with summary data inTable 11. For all horses two non-impacted areas of cartilage wereexamined in each joint; the lateral trochlear ridge of the talus, andthe distal intermediate ridge of the tibia, which is the opposing jointsurface that articulates with the impacted region on the medialtrochlear ridge. Both samples were examined, then a single score wasassigned for non-impacted cartilage. For all horses, focal regions ofthe medial trochlear ridge containing each of the three impacts wereexamined, then a single score was assigned for impacted cartilage foreach joint.

General Observations—Impacted Cartilage: As expected, all impacted areasof cartilage had moderately to severely abnormal cartilage scores.

Total Joint Scores: The results show that MSC treatment led tosignificantly better score for fissuring/fibrillation. All othercomponent scores as well as the total score were also better in thetreated group (Table 11) as compared to control.

Cartilage Fissuring/Fibrillation: Treated joints has a significantlylower (better) score for fibrillation/fissuring (FIG. 12 , p=0.039,one-tailed t-test) and for delta fibrillation/fissuring (p=0.030,one-tailed t-test). This finding demonstrates that treated joints hadless structural damage in areas of injury than controls.

Additional Observations: Cartilage clefts were noted to be healed inseveral slides, subjectively more often in treated limbs. Thishealing-type response has not been previously noted in this animal modelof post traumatic osteoarthritis. Subchondral bone sclerosis can beobserved in numerous slides as well.

TABLE 11 Osteochondral histology component and total scores. Datarepresent mean ± S.E. Cell cluster/ Fibrillation/ chondrone fissuringFocal cell Total joint Limb formation of cartilage loss GAG loss scoreControl 3.57 ± 0.30 3.14 ± 0.55 3.00 ± 0.44 3.28 ± 0.36 13.00 ± 1.15Treatment 3.14 ± 0.34 2.29 ± 0.29 2.57 ± 0.37 3.14 ± 0.34 11.14 ± 1.09

F. Osteochondral Immunohistochemistry (Collagen Type I and II) Results

Immunohistochemisty for collagens type I and II was performed onosteochondral sections (FIG. 11 ). India ink staining was also performed(FIG. 13 ). No quantitative assessment of the immunohistochemistrysections was performed due to the inherently high variability in theassay.

Collagen Type I—Non-impacted (remote) cartilage: Immunohistochemistryfor collagen type I was largely unremarkable in the remote controlsamples in both the treated and untreated control limbs with no collagentype I staining of the articular cartilage.

Collagen Type I—Impacted cartilage: Staining for collagen type I wasconfined to regions of impact and generally extended ¼-½ into thearticular cartilage surface. There were very few changes and no observeddifferences between treatment and control limbs. In regions of repairtissue (noted above in “Additional Subjective Observations”, stainingwas only noted in the deeper ½ of the repair tissue).

Collagen Type II—Non-impacted (remote) cartilage: Immunohistochemistryfor collagen type II was largely unremarkable in the control sampleswith even distribution of collagen type II throughout the cartilage.

Collagen Type II—Impacted cartilage: There were few areas of collagentype II loss in control or treated joints. In the immediate region ofthe impacts, there was slightly reduced staining for collagen type II.Similar to collagen type I, areas of fibrous repair only stained forcollagen type II in the deeper layers of the repair tissue.

Immunomodulatory Chemokines: The most MSC-specific finding in the studywas the increased PGE-2 concentration in Eq12a10+0.1 MSCs treated jointscompared to controls. PGE-2 modulates chemokines and chemotaxis ofpro-inflammatory cells and is therefore a key mediator ofimmunopathology. All cells are capable of producing PGE-2, and MSCs areknown to increase the expression of PGE-2 by myeloid and stromal cells.In this study, PGE-2 concentration in synovial fluid peaked at day 28and then decreased for the remainder of the study.

Conclusion: This pre-clinical study supports the use of Eq12a10+0.1 MSCsfor the treatment of post-traumatic osteoarthritis. The treatment issafe and there is strong evidence to suggest it may be efficacious inmitigating the effects of joint trauma. For example, cartilage cleftswere noted to be healed in several slides, subjectively more often intreated limbs. This healing-type response has not been previously notedin this animal model of post traumatic osteoarthritis

Example 6 Immunosuppression

The immunosuppression capacity of equine integrin α10 selected MSCsisolated from adipose tissue was also tested. The immunosuppressionassay was conducted by having peripheral blood mononuclear cells (PBMC)stimulated with Concanavalin A for 72 hours in co-cultures withallogenic MSCs at different ratios. Lymphocyte proliferation wasmeasured by adding bromodeoxyuridine (BrdU) 24 hours before flowcytometry analysis of the BrdU incorporation to measure of lymphocyteproliferation. Shown in FIG. 14 is the frequency of BrdU positive CD4expressing T cells.

Conclusion: equine integrin α10 selected MSCs isolated from adiposetissue have an immunomodulatory capacity on T cells, demonstrated as adecrease in lymphocyte proliferation with increasing ratios of MSCs toPBMCs. The greatest immunosupressive effect was generated at one MSC toone PBMC ratio.

Equivalents

The foregoing written specification is considered to be sufficient toenable one skilled in the art to practice the embodiments. The foregoingdescription and Examples detail certain embodiments and describes thebest mode contemplated by the inventors. It will be appreciated,however, that no matter how detailed the foregoing may appear in text,the embodiment may be practiced in many ways and should be construed inaccordance with the appended claims and any equivalents thereof.

As used herein, the term about refers to a numeric value, including, forexample, whole numbers, fractions, and percentages, whether or notexplicitly indicated. The term about generally refers to a range ofnumerical values (e.g., +/−5-10% of the recited range) that one ofordinary skill in the art would consider equivalent to the recited value(e.g., having the same function or result). When terms such as at leastand about precede a list of numerical values or ranges, the terms modifyall of the values or ranges provided in the list. In some instances, theterm about may include numerical values that are rounded to the nearestsignificant figure.

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1.-69. (canceled)
 70. An enriched integrin α10 population ofundifferentiated cells, wherein at least 60% of the cells of thepopulation express integrin α10 subunit, wherein the cells are WWIInegative and CD45 negative, and wherein the cells are selected frommesenchymal stem cells (MSCs), mesenchymal progenitor cells, andmesenchymal stromal cells.
 71. The enriched integrin α10 population ofclaim 70, wherein the cells are autologous or allogenic.
 72. Theenriched integrin α10 population of claim 70, wherein at least 65%, atleast 70%, at least 75%, at least 80%, at least 85%, at least 90%, atleast 95%, at least 96%, at least 97%, at least 98%, at least 99%, or100% of the total cells comprised in the population express integrin α10subunit.
 73. The enriched integrin α10 population of claim 70, whereinsaid population is an in vitro cell culture.
 74. The enriched integrinα10 population of claim 70, wherein the cells that express integrin α10are isolated with an anti-integrin α10 antibody.
 75. The enrichedintegrin α10 population of claim 74, wherein the anti-integrin α10antibody is a monoclonal antibody.
 76. The enriched integrin α10population of claim 70, wherein the cells are derived from adiposetissue, bone marrow, synovial membrane, peripheral blood, cord blood,umbilical cord blood, Wharton's jelly, or amniotic fluid.
 77. Theenriched integrin α10 population of claim 70, wherein the MSCs expressCD44, CD90 and CD105.
 78. A method of delaying or stopping the onset ofsubchondral bone sclerosis, damage due to traumatic joint injuries,and/or degenerative joint disease (DJD) in a mammal in need thereof,comprising injecting a therapeutically effective amount of the enrichedintegrin α10 population of cells of claim 70 into a damaged joint and/orbone of the mammal.
 79. The method of claim 78, wherein the degenerativejoint disease (DJD) is selected from subchondral bone disease, cartilagedegeneration, post-traumatic osteoarthritis, inflammatory arthritis, andcongenital malformation and/or deformation of the musculoskeletalsystem, and wherein the damage due to traumatic joint injury is selectedfrom osteochondral damage, tendon damage, ligament damage, and muscledamage.
 80. The method of claim 79, wherein the osteochondral damagecomprises articular cartilage damage and/or bone damage.
 81. The methodof claim 79, wherein the osteochondral damage, cartilage damage orinjury is a break, sprain, bruise, tear, fracture, rupture, a cartilagefissure, a cartilage microfracture, a chondral defect, a tendon rupture,a ligament rupture, or a bone fracture, and/or wherein the osteochondraldamage, cartilage damage or injury in the joint is in a muscle, tendon,bone, ligament, cartilage, or meniscus.
 82. The method of claim 78,wherein the population of cells comprise MSCs that are formulated into acell aggregate prior to intra-articular injection.
 83. The method ofclaim 78, wherein the mammal is a human, horse, pony, ox, donkey, mule,camelid, cat, dog, pig, or cow.
 84. A method of manufacturing anenriched integrin α10 population of undifferentiated cells selected frommesenchymal stem cells (MSCs), mesenchymal progenitor cells, andmesenchymal stromal cells, wherein at least 60% of the cells of thepopulation express integrin α10 subunit, the method comprising: (a)isolating a population of stem cells from adipose tissue, bone marrow,synovial membrane, cord blood, Wharton's jelly, or amniotic fluid; (b)culturing the isolated cells in a plastic culture vessel; (c) discardingnon-adhered cells; (d) inducing integrin α10 expression by addingculture media, wherein the culture media is a serum-free media or amedia comprising mammalian serum, and wherein the culture mediacomprises platelet lysate; (e) selecting the cells that express integrinα10, and (f) expanding the selected cells, thereby producing an enrichedintegrin α10 population of undifferentiated cells selected frommesenchymal stem cells (MSCs), mesenchymal progenitor cells, andmesenchymal stromal cells.
 85. The method of claim 84, wherein theculture media in step (d) comprises fibroblast growth factor 2 (FGF2)and/or transforming growth factor beta (TGFβ).